Preparing to remove a foreign bus connection between a service integration bus and a WebSphere MQ network

Before you remove a foreign bus connection between a service integration bus and a WebSphere MQ network, drain as many messages as we can from the link transmitter queue, then manually move or delete any remaining messages.

We must know which foreign bus connection is being prepared for deletion. You should also inform the WebSphere MQ administrator that the foreign bus connection is about to be deleted and therefore no longer paired with its WebSphere MQ gateway queue manager or message broker in the WebSphere MQ network.

When a foreign bus connection is deleted from the configuration, the next time the hosting messaging engine for a link transmitter is started, it deletes all its messages or moves them to the exception destination. To avoid messages being unintentionally deleted or moved to the exception destination, drain as many messages as possible from the link transmitter queue. Then, before we delete the link configuration, either move any remaining messages to an exception destination or delete them.

If there are publish/subscribe broker profiles defined, you should remove the subscriptions.

1. Start the console.

2. Optional: If there are publish/subscribe broker profiles defined on any of the links for this foreign bus connection, remove the subscriptions.

   Complete the following substeps for each broker profile:

   1. Navigate to Service integration -> Buses -> bus_name -> [Topology] Foreign bus connections -> foreign_bus_name -> [Related Items] WebSphere MQ links -> link_name -> [Additional Properties] Publish/subscribe broker profiles -> profile_name

   2. Click the Runtime tab.

   3. Click Subscriptions.

   4. Click Unsubscribe to remove all the subscriptions listed.
   When an unsubscribe command is sent to the message broker in the WebSphere MQ network, the relevant topic mapping is put into an indoubt state until the unsubscribe is confirmed when the topic mapping is deleted. After the unsubscribe is confirmed, the topic mapping is no longer shown in the runtime view. We might have to refresh the runtime view for all subscriptions to be shown as removed.

3. Prevent new messages from being produced for this foreign bus connection.

   1. Navigate to Service integration -> Buses -> bus_name -> [Topology] Foreign bus connections -> foreign_bus_name

   2. Under General properties, clear the Send Allowed check box.

   3. Click Apply to save the configuration.

4. Determine when there are no more messages queued, then stop the link to the foreign bus in a controlled manner.

   1. Under Related Items, click WebSphere MQ links to display the list of links for this bus.

   2. Click the Refresh icon of Status to refresh the view of the current outbound messages.

   3. When there are no current outbound messages, select the check box next to the appropriate link and then select a Stop mode of "Quiesce".

   4. Select a Target state of "Stopped" so that the link can only be started again by administrator action.

   5. When the status of the link turns to red, the link to the foreign bus has no remaining messages and is stopped.

5. The foreign bus can continue to produce messages after the foreign bus connection on the local bus has been deleted. Because the foreign bus is a WebSphere MQ network, refer to the WebSphere MQ Intercommunication guide for details about the safe deletion of channels at Manage WebSphere MQ channels.

6. Save the changes to the master configuration.
   

Results

You have removed the subscriptions from any publish/subscribe brokers on the link. You have drained as many messages as possible from the link transmitter queue, and either moved any remaining messages from the transmission queues to an exception destination or deleted them.

What to do next

We are now ready to remove the foreign bus connection.

Related tasks

Manage pending acknowledgement messages on a deleted WebSphere MQ link

Manage messages in a link transmission queue for a connection to a WebSphere MQ network

Administer an existing WebSphere MQ link

Delete a WebSphere MQ link publish/subscribe broker profile